*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
.xxk{
    width: 280px;
    margin: 0 auto;
    margin-top: 30px;
    background: #e6e6e6;
}
.nav::after{
    display: table;
    content: "";
    clear: both;
}
.nav li{
    float: left;
    list-style: none;
    margin-left: 10px;
    margin-right: 10px;
    text-align: center;
    cursor: pointer;
}
.nav li:hover{
    color: red;
}
.nav li.active{
    padding-bottom: 5px;
    border-bottom: 2px solid #F40;
}
.main{
    padding-top: 20px;
}
.main>div{
    display: none;
}
.main>div.active{
    display: block;
}
a{
    color: #000;
    font-size: 12px;
    text-decoration: none;
}
.l1{
    color: #ff5000;
}
.main div::after{
    display: table;
    content: "";
    clear: both;
}
.main div ul{
    float: left;
}
.main div ul:nth-child(2){
    padding-left: 20px;
}
.main div ul li{
    list-style: none;
    font-size: 12px;
    line-height: 25px;
}